A sex abuse victim advocate says employers can learn from the Labour Party sexual assault allegations.

A QC investigation did not substantiate assault or harassment allegations against a former party staffer.

Louise Nicholas says employers should know what support a complainant might need, even if a formal complaint isn't made.

She told Tim Dower processes should be clear for all parties involved.

"Seek advice. Don't take it on your self as your not the expert, and it can turn into custard, and that's what we don't want for either party."

She says the case wasn't approached correctly and she wants more clarity about who investigates such allegations, as victims need conclusions.

"They need to do something, so what is that something and who is that someone they can go to."